31143430440021 has 4 divisors (see below), whose sum is σ = 41524573920032. Its totient is φ = 20762286960012.

The previous prime is 31143430440019. The next prime is 31143430440149. The reversal of 31143430440021 is 12004403434113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 31143430440021 - 2¹ = 31143430440019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31143430440821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5190571740001 + ... + 5190571740006.

It is an arithmetic number, because the mean of its divisors is an integer number (10381143480008).

Almost surely, 2^{31143430440021} is an apocalyptic number.

It is an amenable number.

31143430440021 is a deficient number, since it is larger than the sum of its proper divisors (10381143480011).

31143430440021 is a wasteful number, since it uses less digits than its factorization.

31143430440021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10381143480010.

The product of its (nonzero) digits is 13824, while the sum is 30.

Adding to 31143430440021 its reverse (12004403434113), we get a palindrome (43147833874134).

The spelling of 31143430440021 in words is "thirty-one trillion, one hundred forty-three billion, four hundred thirty million, four hundred forty thousand, twenty-one".